This invention relates to an improvement in a construction of a power train of a vehicle.
As a conventional construction of a vehicle power train, Japanese Patent Application Laying Open Gazette No. 1-313630 and German Patent Application Unexamined Gazette No. DE3838073 disclose that an engine and a transmission are in parallel with each other in a longitudinal direction of a vehicle, namely the engine is so arranged that an axial direction of a crankshaft thereof accords with a car-width direction and the transmission is so arranged at a rear of the engine that a shaft of the transmission is in parallel with the crankshaft of the engine. In both references, a front-wheel shaft and a differential for front wheels are disposed under the transmission.
However, in the power train construction having the engine and transmission which are in parallel with each other and the front-wheel differential, while a case of the transmission is integrally formed with a cylinder block of the engine, the transmission and the engine moves toward and away from each other at a delicately connected part of an integrally formed part thereof, namely, an open/close mode movement is caused owing to each independent movement of the transmission and the engine around respective principal shaft of inertia as centers. As a result, a distance between the crankshaft of the engine and an output shaft of the transmission is varied. Similarly, the respective open/close mode movements between the engine and the front-wheel differential and between the front wheel differential and the transmission are also caused. Therefore, vibration of the whole power train can be prevented insufficiently, and a power transmitting performance to a drive wheel is lowered.